A method and a device for checking an ideal position of a cooking pot above an induction coil of an induction cooking hob

Abstract

 The present invention relates to a method for checking an ideal position of a cooking pot (20) above an induction coil (14) of an induction cooking hob (10), wherein said method includes the following steps:
a) starting the method for checking the ideal position,
b) detecting a first parameter related to the power of the electromagnetic field and/or to the position of the cooking pot (20) above the induction coil (14),
c) detecting a second parameter related to the power of the electromagnetic field and/or to the position of the cooking pot (20) above the induction coil (14),
d) comparing the detected first and second parameters with a stored relationship between said first and second parameters and the position of the cooking pot (20) above the induction coil (14),
e) determining a deviation of the position of the cooking pot (20) from the ideal position above the induction coil (14),
f) performing periodic repetitions of the steps b) to e) after a predetermined time, and
g) outputting at least one signal corresponding with the deviation of the position of the cooking pot (20) from the ideal position, if said deviation exceeds a minimum value.
Further, the present invention relates to an induction cooking hob (10) including a system for checking an ideal position of a cooking pot (20) above an induction coil (14) of said induction cooking hob (10).

Description

[0001] The present invention relates to a method for checking an ideal position of a cooking pot above an induction coil of an induction cooking hob. Further, the present invention relates to an induction cooking hob including a system for checking an ideal position of a cooking pot above an induction coil of said induction cooking hob.

[0002] A wrong or an inappropriate position of a cooking pot above an induction coil may cause a suboptimal cooking process. The wrong or inappropriate position of the cooking pot reduces the power transfer from the induction coil to said cooking pot. Further, the wrong or inappropriate position of the cooking pot may avoid an even browning of the foodstuff. Moreover, the wrong or inappropriate position of the cooking pot may cause slow heat up times. Additionally, the wrong or inappropriate position of the cooking pot may cause a too high power transfer into critical areas of the cooking pot, for example into the side walls of the cooking pot, resulting in damages.

[0003] However, the user often cannot recognize the ideal position of the cooking pot above the induction coil. It would be advantageous to check the ideal position of the cooking pot above the induction coil of the induction cooking hob.

[0004] It is an object of the present invention to provide a method and a system for checking an ideal position of a cooking pot above an induction coil of an induction cooking hob by low complexity. This is achieved by the method for checking an ideal position of a cooking pot above an induction coil of an induction cooking hob according to claim 1.

[0005] The method of the present invention includes the following steps:

a) starting the method for checking the ideal position,

b) detecting a first parameter related to the power of the electromagnetic field and/or to the position of the cooking pot above the induction coil,

c) detecting a second parameter related to the power of the electromagnetic field and/or to the position of the cooking pot above the induction coil,

d) comparing the detected first and second parameters with a stored relationship between said first and second parameters and the position of the cooking pot above the induction coil,

e) determining a deviation of the position of the cooking pot from the ideal position above the induction coil,

f) performing periodic repetitions of the steps b) to e) after a predetermined time, and

g) outputting at least one signal corresponding with the deviation of the position of the cooking pot from the ideal position, if said deviation exceeds a minimum value.

[0006] The main idea of the present invention bases on the fact that the power of the electromagnetic field is maximal, if the cooking pot is in an ideal position above the induction coil. In contrast, the power of the electromagnetic field decreases, if the position of the cooking pot deviates from said ideal position. Thus, the detections of parameters related to the power of the electromagnetic field provide information about the deviation from the ideal position of the cooking pot. The method may be performed by components, which are already available in the induction cooking hob.

[0007] Preferably, the first parameter is a current through the induction coil. The current through the induction coil can be detected by components, which are already available in the induction cooking hob.

[0008] In particular, the second parameter is a phase difference between the current through the induction coil and a voltage at said induction coil. Also the voltage and therefore the phase difference can be detected by already available components of the induction cooking hob.

[0009] Another parameter may be the frequency change of the current through the induction coil and/or of the voltage at said induction coil. Said frequency change may occur during a displacement of the cooking pot above the induction coil.

[0010] A further parameter may be the difference between a desired value and an actual value of the power of the electromagnetic field. For example, said desired value may be stored in a memory device or in a user interface.

[0011] Moreover, the current profile through the induction coil may be used as parameter. In particular, the deviation of the current profile from the sinusoidal signal is internally detectable. The deviation of the current profile from the sinusoidal signal may be used for evaluating the deviation of the position of the cooking pot from the ideal position above the induction coil.

[0012] Alternatively or additionally, a further parameter may be a setting parameter of the induction coil and/or the frequency at the induction coil.

[0013] For example, the method may be started by operating an actuator of a user interface.

[0014] Preferably, the method is manually started by operating the actuator of the user interface.

[0015] Further, a power of the electromagnetic field generated by the induction coil may be detected and used for the determination of the deviation of the position of the cooking pot.

[0016] Moreover, the predetermined time between subsequent periodic repetitions of the steps b) to e) is between 0.1 s and 1.0 s, preferably 0.5 s.

[0017] Preferably, the signal is an optical, acoustic and/or mechanical signal.

[0018] The object of the present invention is further achieved by the induction cooking hob including a system for checking an ideal position of a cooking pot above an induction coil of said induction cooking hob according to claim 7.

[0019] The system for checking the ideal position of the cooking pot above the induction coil includes:

• a first detection device for detecting a first parameter related to the power of the electromagnetic field and/or to the position of the cooking pot above the induction coil,
• a second detection device for detecting a second parameter related to the power of the electromagnetic field and/or to the position of the cooking pot above the induction coil,
• a control unit for comparing the detected first and second parameters with a stored relationship between said first and second parameters and the position of the cooking pot above the induction coil, for determining a deviation of the position of the cooking pot from the ideal position above the induction coil, and for performing periodic repetitions of the detections, comparison and determination after a predetermined time, and
• an output device for outputting at least one signal corresponding with the deviation of the position of the cooking pot from the ideal position.

[0020] The invention bases on the effect, that the power of the electromagnetic field is maximal only, if the cooking pot is in an ideal position above the induction coil. In contrast, the power of the electromagnetic field decreases, if the position of the cooking pot deviates from said ideal position. Thus, the detections of the parameters related to the power of the electromagnetic field provide information about the deviation from the ideal position of the cooking pot. The system may use components, which are already available in the induction cooking hob.

[0021] Preferably, the first detection device is provided for detecting a current through the induction coil.

[0022] In particular, the second detection device is provided for detecting a phase difference between the current through the induction coil and a voltage at said induction coil.

[0023] Additionally or alternatively, the first and/or second detection devices may be provided for detecting a setting parameter of the induction coil and/or the frequency at the induction coil.

[0024] Further, the induction cooking hob may comprise an actuator for starting a method for checking the ideal position of the cooking pot above the induction coil. Preferably, the actuator is a part of a user interface of the induction cooking hob. Thus, a user can manually start the method for checking the ideal position.

[0025] Additionally, the induction cooking hob comprises a detection device for detecting a power of an electromagnetic field generated by the induction coil.

[0026] Moreover, the output device may include at least one display, a sound generator and/or a mechanical indicator.

[0027] Furthermore, the induction cooking hob may include a user interface, wherein at least one component of the output device is an integrated part of said user interface.

[0028] For example, the output device includes at least one seven-segment display, wherein the number of the activated segments corresponds with the deviation of the position of the cooking pot from the ideal position above the induction coil.

[0029] At last the present invention relates to a computer program product stored on a computer usable medium, comprising computer readable program means for causing a computer to perform the method mentioned above.

[0030] Novel and inventive features of the present invention are set forth in the appended claims.

[0031] The present invention will be described in further detail with reference to the drawings, in which

FIG 1

illustrates a schematic top view of an induction cooking hob according to a preferred embodiment of the present invention, and

FIG 2

illustrates a further schematic top view of the induction cooking hob according to the preferred embodiment of the present invention.

[0032] FIG 1 illustrates a schematic top view of an induction cooking hob 10 according to a preferred embodiment of the present invention.

[0033] The induction cooking hob 10 includes a cooking panel 12, induction coils 14 and a user interface 16. The induction coils 14 are arranged below the cooking panel 12. In this example, the induction cooking hob 10 includes four induction coils 14. The cooking panel 12 comprises four cooking zones corresponding with one induction coil 14 in each case. In this example, the cooking zones and the corresponding induction coils 14 are circular. In general, the cooking zones and the induction coils 14 may have other geometrical shapes. In this preferred embodiment, the induction cooking hob 10 includes two front induction coils 14 and two rear induction coils 14. The both front induction coils 14 are arranged side by side. In a similar way, the both rear induction coils 14 are also arranged side by side.

[0034] The user interface 16 comprises control elements. Said control elements are provided for activating and deactivating the induction coils 14. Further, the control elements are provided for adjusting the power of the induction coils 14. Moreover, the user interface 16 comprises an actuator for starting a method for checking the ideal position of the cooking pot above the induction coil. Additionally, the user interface 16 may comprise one or more display elements. Said display elements are provided for indicating activated and/or deactivated states of the induction coils 14. Moreover, the display elements are provided for indicating the power of the induction coils 14.

[0035] A cooking pot 20 is arranged upon one of the cooking zones. The cooking pot 20 is arranged concentrically above the left rear induction coil 14. The concentric arrangement of the cooking pot 20 above the induction coil 14 allows a maximum power of the electromagnetic field generated by said induction coil 14. Said concentric arrangement above the induction coil 14 is the ideal position of the cooking pot 20. Since the base area of the cooking pot 20 is bigger than the induction coil 14, the cooking pot 20 covers completely the induction coil 14.

[0036] FIG 2 illustrates a further schematic top view of the induction cooking hob 10 according to the preferred embodiment of the present invention.

[0037] The induction cooking hob 10 and the cooking pot 20 are the same as in FIG 1. However, the position of the cooking pot 20 in FIG 2 is displaced relating to the left rear induction coil 14. The cooking pot 20 does not completely cover the induction coil 14. The power of the electromagnetic field generated by the induction coil 14 is smaller than in FIG 1, since the cooking pot 20 is not concentrically arranged above the left rear induction coil 14.

[0038] The induction cooking hob 10 includes a system for checking the ideal position of the cooking pot 20 above the induction coil 14. The system includes at least two detection devices for detecting parameter values relating to the power of the electromagnetic field and/or to the position of the cooking pot above the induction coil. Preferably, said parameter values are the current through the induction coil and the phase difference between said current and a voltage at said induction coil.

[0039] Moreover, the system includes a memory device. A relationship between the parameter values and a deviation of the cooking pot 20 from the ideal position above the induction coil 14 is stored in said memory device. The detected parameter values are compared with the relationship stored in the memory device by a control unit of the induction cooking hob 10. The deviation of the cooking pot 20 from the ideal position can be determined from the detected parameter values.

[0040] Furthermore, the actual detected parameter values are stored in the memory device. Said detected parameter values remain stored at least during the actual cooking process. Optionally, the detected parameter values remain stored after the cooking process has been finished and may be used as reference values for later cooking processes.

[0041] Preferably, a method for checking for checking the ideal position of the cooking pot above the induction coil is manually started by operating the actuator of the user interface 16 by a user. A first parameter and second parameter related to the power of the electromagnetic field and/or to the position of the cooking pot above the induction coil are detected. The detected first and second parameters are compared with a stored relationship between said first and second parameters and the position of the cooking pot above the induction coil. Then, a deviation of the position of the cooking pot from the ideal position above the induction coil is determined. The above detections, comparison and determination are periodically repeated after a predetermined time. At last, one or more signals corresponding with the deviation of the position of the cooking pot from the ideal position are output, if said deviation exceeds a minimum value.

[0042] Preferably, the parameters are the current through the induction coil and the phase difference between the current through the induction coil and the voltage at said induction coil. The current and the voltage and therefore the phase difference can be detected by already available components of the induction cooking hob 10.

[0043] A further parameter may be the frequency change of the current through the induction coil 14 and/or of the voltage at said induction coil 14. Said frequency change may occur during a displacement of the cooking pot 20 above the induction coil 14.

[0044] Another parameter may be the difference between a desired value and an actual value of the power of the electromagnetic field. For example, said desired value may be stored in a memory device or in the user interface 16.

[0045] Further, the current profile through the induction coil 14 may be used as parameter. For example, the deviation of the current profile from the sinusoidal signal is internally detectable. The deviation of the current profile from the sinusoidal signal may be used for evaluating the deviation of the position of the cooking pot 20 from the ideal position above the induction coil 14.

[0046] The predetermined time between subsequent periodic repetitions of the detections, comparison and determination is between 0.1 s and 1.0 s, preferably 0.5 s.

[0047] Furthermore, the system includes an output device for a signal indicating that the cooking pot 20 deviates from the ideal position and/or that the cooking pot 20 is in the ideal position. The output device provides an optical, acoustic and/or mechanical signal. The output device may be an integrated part of the user interface 16. For example, the output device includes a seven-segment display, wherein the horizontal lines of said seven-segment display indicate the deviation of the cooking pot 20. In this case, one activated horizontal line corresponds with a bad position of the cooking pot 20. Two activated horizontal lines correspond with an acceptable position of the cooking pot 20. Three activated horizontal lines correspond with a perfect position of the cooking pot 20.

[0048] The present invention allows the user an opportunity to check the position of the cooking pot above the induction coil. The user gets the opportunity to place the cooking pot in the ideal position of the cooking pot above the induction coil in order to optimize the cooking results. The ideal position of the cooking pot allows an even browning of the foodstuff. Further, the ideal position of the cooking pot allows a good power transfer into the bottom of the cooking pot resulting in fast heat up times. The user is guided by the indication how to place the cooking pot on the ideal position.

[0049] Although an illustrative embodiment of the present invention has been described herein with reference to the accompanying drawings, it is to be understood that the present invention is not limited to that precise embodiment, and that various other changes and modifications may be affected therein by one skilled in the art without departing from the scope or spirit of the invention. All such changes and modifications are intended to be included within the scope of the invention as defined by the appended claims.

List of reference numerals

[0050] 

10

induction cooking hob

12

cooking surface

14

induction coil

16

user interface

20

cooking pot

Claims

1. A method for checking an ideal position of a cooking pot (20) above an induction coil (14) of an induction cooking hob (10), wherein said method includes the following steps:

a) starting the method for checking the ideal position,

b) detecting a first parameter related to the power of the electromagnetic field and/or to the position of the cooking pot (20) above the induction coil (14),

c) detecting a second parameter related to the power of the electromagnetic field and/or to the position of the cooking pot (20) above the induction coil (14),

d) comparing the detected first and second parameters with a stored relationship between said first and second parameters and the position of the cooking pot (20) above the induction coil (14),

e) determining a deviation of the position of the cooking pot (20) from the ideal position above the induction coil (14),

f) performing periodic repetitions of the steps b) to e) after a predetermined time, and

g) outputting at least one signal corresponding with the deviation of the position of the cooking pot (20) from the ideal position, if said deviation exceeds a minimum value.

2. The method according to claim 1,
characterized in that
the first parameter is a current through the induction coil (14) .

3. The method according to claim 1 or 2,
characterized in that
the second parameter is a phase difference between the current through the induction coil (14) and a voltage at said induction coil (14).

4. The method according to any one of the preceding claims,
characterized in that
the method is started by operating an actuator of a user interface.

5. The method according to claim 4,
characterized in that
the method is manually started by operating the actuator of the user interface.

6. The method according to any one of the preceding claims,
characterized in that
a power of the electromagnetic field generated by the induction coil (14) is detected and used for the determination of the deviation of the position of the cooking pot (20).

7. The method according to any one of the preceding claims,
characterized in that
the predetermined time between subsequent periodic repetitions of the steps b) to e) is between 0.1 s and 1.0 s, preferably 0.5 s.

8. An induction cooking hob (10) including a system for checking an ideal position of a cooking pot (20) above an induction coil (14) of the induction cooking hob (10), wherein said system includes:

- a first detection device for detecting a first parameter related to the power of the electromagnetic field and/or to the position of the cooking pot (20) above the induction coil (14),

- a second detection device for detecting a second parameter related to the power of the electromagnetic field and/or to the position of the cooking pot (20) above the induction coil (14),

- a control unit for comparing the detected first and second parameters with a stored relationship between said first and second parameters and the position of the cooking pot (20) above the induction coil (14), for determining a deviation of the position of the cooking pot (20) from the ideal position above the induction coil (14), and for performing periodic repetitions of the detections, comparison and determination after a predetermined time, and

- an output device for outputting at least one signal corresponding with the deviation of the position of the cooking pot (20) from the ideal position.

9. The induction cooking hob according to claim 8, characterized in that
the first detection device is provided for detecting a current through the induction coil (14).

10. The induction cooking hob according to claim 8 or 9, characterized in that
the second detection device is provided for detecting a phase difference between the current through the induction coil (14) and a voltage at said induction coil (14).

11. The induction cooking hob according to any one of the claims 8 to 10,
characterized in that
the induction cooking hob (10) comprises an actuator for starting a method for checking the ideal position of the cooking pot (20) above the induction coil (14).

12. The induction cooking hob according to any one of the claims 8 to 11,
characterized in that
the induction cooking hob (10) comprises a detection device for detecting a power of an electromagnetic field generated by the induction coil (14).

13. The induction cooking hob according to any one of the claims 8 to 12,
characterized in that
the output device includes at least one display, a sound generator and/or a mechanical indicator.

14. The induction cooking hob according to any one of the claims 8 to 13,
characterized in that
the induction cooking hob (10) includes a user interface (16), wherein at least one component of the output device is an integrated part of said user interface (16).

15. The induction cooking hob according to any one of the claims 7 to 14,
characterized in that
the output device includes at least one seven-segment display, wherein the number of the activated segments corresponds with the deviation of the position of the cooking pot (20) from the ideal position above the induction coil (14).

Drawing